1. Field of the Invention
This invention relates to a Ni-Si alloy for spark plug electrodes with high heat resistance and low wear which contains a small amount of Cr-Al, Cr-Al-Y, Al-Y or Cr-Y. The invention further relates to a nickel alloy for spark plug electrodes with good characteristics which contains not more than about 0.5 wt % of Mn as a deoxidizing agent.
2. Description of the Prior Art
A nickel alloy for use in spark plug electrodes must be resistant to (1) oxidative wear, (2) spark wear, and (3) corrosion by internal combustion residues typified by PbO. In addition, a Ni electrode with a copper core which has recently been developed to expand the utility (heat range) of spark plugs must have high plastic workability. Consequently, this new type of Ni electrode can only accommodate up to about 3 wt % of additives, and the use of elements which do not contribute to improve the properties of the alloy must be minimized.